This invention relates to the creation of an illusion of motion employing standard size photographic slide transparencies and more particularly to a photographic slide assembly which may be utilized to project images having an illusion of motion and to a projection system use therewith.
Photographic slide projectors, such as the standard gravity fed 35 mm. carrousel-type projector, have been known for many years and are utilized to project stationary images on a screen from photographic slide transparencies. While various techniques have been utilized in other areas for producing illusions of motion through the use of polarization and moire patterning, these prior techniques have not been adaptable to conventional photographic slide projection.
In U.S. Pat. Nos. 3,643,361 and 3,811,213 issued to the present applicant, apparatus and methods for the creation of an illusion of motion by moire patterning are disclosed. In U.S. Pat. No. 3,827,797, also to the present applicant, an adapter or attachment mechanism is disclosed for use in standard overhead projectors for creating an illusion of motion with the use of dot pattern transparencies. In prior devices such as that shown in U.S. Pat. No. 3,827,797, an activator sheet carrying a dot pattern is mounted to the display device independent of the removable and changeable transparencies which comprise a cooperating "art sheet".